I would like to ask an experienced person.
How did you move your SharePoint Online Modern Team Site list, library settings and SPFX programs from development to test and from test to production?
To move the lists and libraries between environment, I would suggest you use the mover tool. Please read this article for more:
For SPFX solutions, you could download them from the test environment. Then deploy them on your product environemnt.
You have to use the 3rd party tools to migrate / move content between the SharePoint tenants. Their is no OOTB way, you can try different tools as they offer free trail
Another way is using the Save as template method.
- Save the source site as a template
- Then attach the saved template to the destination site in SharePoint Online
- Copy the content from source site to the destination site in SharePoint Online